Sulphonic acid and process for producing it



Patented Nov. 23, 1943 UNITED" STATES PATENT OFFICE SULPHONIO ACID AND PROCESS FOR PBODUCIN G Paul Nawiaaky, S

SprengenWeatileld,

Delaware nmmit, and Gerhard Ewald N. 1., alaignora to General Aniline a Film Corporation, a corporation of lclaims.

This invention relates to the utilization of addition compounds of thioxane with sulphuric acid derivatives. Specifically our invention pertains to the use of addition compounds of thioxane with sulphur trioxide as sulphonating and sulphating agents.

It is a further object of our invention to develop an improved process for sulphonating and sulphating certain classes of organic compounds.

Further objects of our invention may be seen from the detailed description given below.

Addition compounds of thioxane and sulphuric acid derivatives such as sulphur trioxide, chlorsulphonic acid, fluorsulphonic acid, etc. have never been prepared hitherto. These addition compounds are of great importance in industry by reason of the surprising ease with which they react with certain classes of organic compounds such as secondary alcohols to form sulphuric acid esters which are otherwise only obtainable with difllculty, and generally with unsaturated compounds to form organic unsaturated suiphonic acids. As will be shown in greater detail hereinafter, the latter type of compounds cannot be prepared otherwise without the formation of by-products which are often useless waste materials, the separation of which from the useful compounds is difllcult and frequently renders their production commercially unprofitable.

Addition compounds of basic compounds with sulphuric acid derivatives are known and have been used as sulphonating agents, e. g. the addition compound of pyridine with sulphur trioxide (Baumgarten Ber. 59, 1976 (1926)). It is also common knowledge that the undefined addition compounds of alkyl ethers with chlorsulphonic acid or sulphur trioxide are sulphonating agents which are often used in preference to th free sulphuric acid derivatives in spite of the easy inflammability of ethers and the fire hazard thus involved. More recently, the sulphuric acid addition compounds of a cyclic ether, 1-4 dioxane,

have been suggested as an improved sulphonating agent.

We have now'found that 1-4 thioxane of the formula:

CHr

which is a cyclic ether and a weak base in the form of its sulphonium compound, reacts withcertain sulphuric 'acid derivatives in a manner analogous to dioxane, but reacts inan entirely unexpected way with others. Thus it reacts with sulphur trioxide in analogy to dioxane to form coordination compounds such as may be presented by the formulaz CHr-CH! OaS S /CHr-CH1 0.8 (S CHi-CH These products are white solids which are difllcultly soluble in solvents such as benzene, ethylene dichloride and carbon tetrachloride and which compounds are characterized by their surprising stability against heat in that they do not decompose in the above mentioned solvents even when heated to boiling under atmospheric pressure. However, they do decompose easily in water due to hydrolysis to reform unchanged thioxane and sulphuric acid. 0n the other hand, thioxane, in contrast to dioxane reacts in a different way with chlorsulphonic acid, by partly decomposing the chlorsulphonic acid into sulphur trioxide \and hydrochloric acid. The formed sulphur trioxide adds to thioxane to give the coordination compounds while the hydrochloric acid escapes from the reaction mixture. If dioxane, under similar circumstances is used, no evolution of hydrochloric and acid takes place. This difference in the reaction of thioxane and dioxane with chlorsulphonic acid makes the thioxane chlorsulphonic acid reaction product an improved sulphonating agent as compared with the dioxane chlorsulphonic acid reaction product by reason of the removal of substantial amounts of hydrochloric acid, originating from the chlorsulphonic acid, in the case of the use. of thioxane, whereas the hydrochloric acid is not removed at all when dioxane is used. Virtually, therefore, th easily manipulated chlorsulphonic acid, in connection with thioxane, can, for all practical purposes, be substituted for free SO: which is not commercially available as such being supplied only in the form of its solution in sulphuric acid, from which it must be regenerated when its use in the free form is desired. f

Another improvement will become obvious from the use of thioxane as a sulphonating aid. After the completion of a sulphonation reaction it is, in most cases, desirable to remove the sulphonating aid, whether it is pyridine, ethers; acid anhydrides, dioxane or thioxane, from the sulphonated material. The easiest removal in practically all cases is by steam distillation which also removes solvents which may have been used as diluents in the sulphonation. The recovery of pyridine and dioxane from a steam distillation condensate is rendered difllcult by reason of their easy solubility, even miscibility with the water, from which they can only b recovered by salting out or if possible by extraction with waterinsoluble solvents. Thioxane, however, is not miscible, with water and is only slightly soluble in water and can, therefore, be recovered from it by a mere gravity separation, since it is heavier than water and forms the bottom layer in mixtures therewith. This easy and more complete recovery of solvent and sulphonating aid represents a marked improvement in all cases where it is used and may even be a decisive factor in cases where a relatively cheap sulphonated product is obtained.

A further advantage of thioxane is its relatively high boiling point of about 150 C. Dioxane and pyridine have lower boiling points of approximately 100 C. The higher boiling point of thioxm ane facilitates the separation thereof from the solvents such as carbon tetrachloride, benzene and ethylene dichloride which are usually employed in sulphonation processes.

Heretofore sulphonations have been commonly carried out by treating the compounds to be sulphonated with strong sulphuric acid, fuming sulphuric acid, sulphur trioxide, chlorsulphonic acid and the like. We are, of course, aware of other methods of sulphonation, such as treating certain unsaturated compounds, containing carbonyl roups, with bisulphites, and other methods. We are, however, not concerned with such special Frequently, sulphonations of sensitive compounds such as secondary alcohols are carried order to prevent the sulphonation product from decomposing in its acid state. We have now-found that the use of thioxane as a sulphonation aid obviates in many cases the maintenance of'reaction temperatures below room temperature. In

some cases we have found that the use of thioxane as the sulphonation aid permits the sulphonation of certain materials to be conducted at or even above room temperature without the formation of undesired by-products. This is a marked advantage since these reaction temperatures can be easily and inexpensively maintained by coolingwith tap water. Furthermore, we have found that in the presence of thioxane the acid sulphonation products are more stable than in the absence of thioxane under otherwise identical conditions.

This fact demonstrates thatour sulphonation aid is not only beneficial in the sulphonation reaction but even after its completion.

methods and prefer to confine our considerations to common sulphonating agents such as belong to the class which we have enumerated above and which will be referred to later on as "sulphonating agents in a sense that this term will denote such agents whether they are used to form sulphuric acid esters, true sulphonic acids or both.

Th advanced methods of sulphonation comprise reacting the compounds to be sulphonated with sulphonating agents in the presence of solvents which act merely as diluents forthe purpose of delocalizing the reaction and of distributing the heat of the sulphonation reaction. A more advanced method is to treat the compounds in the presence of a sulphonating aid, the purpose of which, generally speaking, is to ease the violence of the sulphonation reaction by bringing the sulphonating agent first into reaction with a sulphonating aid, that is a compound which forms with it an intermediate compound under the evolution of substantial heat of reaction. The intermediate compound subsequently react with the compound to be sulphonated with the evolution of the direct heat of sulphonation diminished by that amount of heat which was evolved in the formation of the intermediat compound. The application of this advanced method of sulphonation in steps generally utilizes the same principle no matter whether pyridine, ethers, dioxane or our preferred material, thioxane, are used as the sulphonation aid.

The present invention in its broad aspect concerns particular methods of carrying out certain sulphonation processes and it will be usefulto demonstrate other advantages which are derived from the use of thioxane as a sulphonation aid.

Our new thioxane sulphur trioxide addition compounds are used advantageously in accordance with our invention to sulphonate various unsaturated olefines. The products of this process are definitely established to be oleiinic solphonic acids. This is shown by the fact that our products are obtained in a substantially qu titative yield from an olefine and sulphur trioxide in the molecular ratio of 1:1. As a consequence of the mildness of our new sulphonation method we are able to practically exclude side reactions. The fact that our products consist of oleflnic sulphonic acids is further proven by analysis and by the fact that our compounds have the ability to add iodine, said addition of iodine being a common reaction for testing for the presence of carbon atoms linked by a double bond. From the foregoing it is clear that in our process the sulphonating agent or sulphur trioxide reacts with the olefine by way of substitution rather than by addition.

Certain surface-active sulphonated derivatives of oleflnic hydrocarbons have been prepared sulphonic acid derivatives of aliphatic saturated hydrocarbons in which a hydroxy group and'a sulphonic acid group occur on the two carbon atoms which in the original olefine were linked through a double bond.

Similar reaction products from olefines, containingnon-terminal double bonds are mentioned in U. 8. Patent 2,098,114. sulphonation products of 2-pentene and of olive oil are described, both of the products obtained by the interaction of sulphur trioxide and an oleflnic material by usingmore than 1 molecule of sulphonating agent for 1 molecule of olefinic material.

In a recent, publication by C'. M. Suter, P. B.

Evans and James M. Kiefer, Journal of the American Chemical Society, 1938. me 538, it is ointed out that by the action of an excess of sulphonating agent on straight chain terminal double bond oleflnes there are primarily formed oleflnic sulphur trioxide addition products of the carbyl sulphate type which may be described by the formula:

BrHUlCHRI-ORHC CH.BI

0 80s 80: \A I in which R1 and Rs may beahydroaen atom or" one of the R's any alkyl group. By hydrolysing this addition compound a compoimdof the type nine. on m 50H OaH may be .obtained, which on further hydrolysis sence of saturated hydrocarbons which may act as diluents during the process of sulphonation. Examples of specific oleflnes useful for conversion into olefine sulphonic acids are; all pentenes or amylenes, all hexenes, heptenes, octenes, nonenes and the like falling within the definition given above.

Such oleflnes may be derived from primary, secondary and tertiary alcohols by dehydration, or

from halogenated hydrocarbons bydehalo'genation or'irom saturated hydrocarbonsthrough cracking or catalytic dehydrogenation, or they may be-obtained'bythedimeriand polymerization of .oleilns such aspropylene, butylenes and isobutylen es, pentenes or amylenes, hexenes and isohexenes and the like. They may also be obtained'by the decarboxylation of unsaturated fatty acids and by many other ways. Also haloforms a hydroxy sulphonic acid of the formula ane-c n m n om ' It would, therefore, appear from this'article that hydroxy sulphonic acid type compounds. when starting from olefinic material, can only be formed by the action of 2 molecules of sulphur trioxide on one molecule of oleiinic material.

It, therefore, appears that in contrast to our gen substituted olefines are suitable in the pursuit of our invention and may be obtained by the con- ,version of unsaturated aliphatic hydroxy compounds into the corresponding halogen compounds, or by the partial dehalogenation of polyhalogenated aliphatic hydrocarbons or by the addition of halohydrides to alkylacetylenes etc.

In preparing the addition products of thioxane and sulphur trioxide which are the subject of our invention we can proceed in various ways. We

' can first prepare the sulphur trioxide addition present process the 'sulphonation of olennic mamany 01' the oleiines which we have found for the production of our new compounds. However, the various types of oleflnes which we have subjected to sulphonation according to our process have all been found to react in a similar way to give, when treated with one molecule .of sulphur trioxide, virtually one molecule of oleflnic sulphonic acid. The types of oleilnes used by us comprise various straight or branch chain oleilnes and tertiary oleilnes having a branch chain on an unsaturated carbon atom. Our sulphonation products, therefore, correspond to the general formula:

where either R1 or B: may be a hydrogen atom or both straight or branch chain substituted or unsubstituted hydrocarbon radicals and at least one x or Y may be-a hydr sen atom and the other a hydrogen atom or a straight or branch chain alkyl radical, but in no case should I. Y and one of the R's be a hydrosen atom at the compound with thioxane preferably in a solvent which is inert to the action of our improved sul phonating agent. Wecan', prepare it by adding sulphur trioxide or chlorosulphonic acid to the solvent and then adding'the mixture .to the thioxane or we can add the sulphonating agent to the solvent-thioxanesmixture. Generally, a white precipitate forms in the reaction mixture which may be employed without further treatment as a sulphonating agent.. The white precipitate may be separated by filtration-and used as'a sulphonating agent to be added to the material to be sulphonated. We can also add the sulphonating agent in the form of sulphur trioxide or preferably chlosame time, one of the hydrogen atoms. either 7 unsaturated hydrocarbons of various molecular weights strals 01181110 75 time were bt ined, after evaporatin flnesandterflaryoleflnesinthepresenceor rosulphonic acid to a mixture of a solvent, thioxane and the material to be sulphonated. For a detailed description of the preparation of the thioxane-sulphur trioxide addition compounds reference is made to our U. 8; Patent No. 2.2191748 dated Oct. 29, 1940, from which this application has been divided. 7

Details of some of the uses to which the thioxanesulphurtrioxide addition compounds may be put will be more clearly demonstrated in the following examples. It is to be understood that the following examples are merely illustrative and our invention is not to be regarded as restricted thereto.. i 1

Example 1.-To a mixture of 350 parts by weight of ethylene-chloride and 52 parts by weight of thioxanethere were added gradually 65 parts by weight of chlorosulphonic acid. To the resultin: reaction mixture, containing the solid addition compound of thioxane and sulphur trioxide. there was added at C. 112 parts by weight of tetra isobutylene, of-the boiling point of 113 C. at 10 mm. obtained by the polymerization of diis'obutylene with activated clay. The solid addition compound dissolved in the course of about one hour and a clear, straw colored solution was obtained. This was neutralized at 10 C. with a caustic soda solution and the neutral mixture heated with steam to remove the solvents. The residual aqueous solution was dried and the residue extracted with methanol. From the extract -methanol, 147 parts by weight of a brittle, somewhat hvdroscopic, white material, which is pure tetra isobutylene sodium sulphonate. The methanol-insoluble-part consisting mainly of mineral salts, amounted to 15 parts by weight.

Example 2.40 parts by weight of sulphur trioxidewere added to a mixture of 350 parts by weight of carbon-tetrachloride and 52 parts by weight of thioxane, while maintaining the reaction temperature at 30 C. Finally 35 parts by weight of 2-pentene were added and the mixture was agitated until all solids had disappeared.

2-pentene sodium sulphonate, which is a ve hygroscopic, glass-like material.

Example 3.-To a sulphonation mixture consisting of the reaction product of 13.5 parts by weight of thioxane 15 parts by weight of chlorosulphonic acid in 38 parts by weight of carbon tetrachloride there were added, at room temperature, 9.8 parts I 64 parts by weight of naphthalene and parts by 52 parts by weight of thioxane there were added at room temperature 65 parts of chlorsulphonic acid.

After agitating for 15 hours, the solution was neutralized. On steam distilling, all the benzene but none of the naphthalene was recovered. The

naphthalene was sulphonated and was recovered in the form of the m-naphthalene sodium sulphonate.

Example 5.To the reaction product of 52 parts by weight of thioxane and 65 parts by weight of chlorosulphonic acid in 450 parts by weight of carbon tetrachloride,

prepared as described in Example 1 of our U. S.

Patent No. 2,219,748, therewere added, at room temperature 120 parts by weight of secondary alcohols.

These alcohols comprised a mixture of secondary alcohols of the probable formula R CHOHR, R and R1 denoting alkyl radicals, containing from 7 to 9 carbon atoms, the mixture having an average hydroxy value of 240. This alcohol mixture was obtained by the hydrogenation of ketones which in turn were prepared by condensing a certain fraction of aliphatic monocarboxylic acids as derived from paraflines by oxidation. The sulphonation of the alcohols, which, as we know, can not be carried out in the absence of sulphonation aids without the formation of un: sulphonated by-products, was completed upon the disappearance of the solid thioxane-sulphur trioxide addition product. The reaction mixture was neutralized by pouring it into a caustic soda solution containing ice. The neutralized mixture separated into two layers, the bottom layer containing the solvents and the sodium salts of sulphuric acid esters of the alcohols and the top After agitating for 24 hours layer consisting of a dilute aqueous mineral salt solution. The bottom layer was separated and steam distilled for the recovery of carbon tetrachloride and thioxane. The residual aqueous liquor was concentrated and yielded 260 parts of a wet paste containing approximately parts of sodium alkyl sulphates which are clearly soluble in water to form surface active solutions.

Eramplgd-I'he solids obtained in Example 1 of our U. S. Patent No. 2,219,748 were charged into a mixture of 370 parts by weight of carbon tetrachloride and 45.3 parts by weight of methallylchloride of the formula CHz:C(CHa)CH:Cl.

The reaction mixture was stirred for 5 hours at 50 C. after which time all of the solids had disappeared. On standing, there appeared instead a viscous oily layer on the solvent which contained chlor-methallyl sulphonic acid. The layer was separated, neutralized with caustic soda solution and dried.

94 parts by weight of a glassy, hygroscopic solid were obtained, the analysis of which indicated it to be sodium sulpho methallyl chloride of the formula N&OaS(CH :C(CH3)CH2C1).

Example 7.Into a mixture of 35 parts of di ethyl ether and 35 parts of chlorosulphonic acid there were charged at atemperature of 5-10 C- 45 parts of oleflnes, obtained by the dehydration of secondary alcohols such as were used in Example #5.

neutral reaction mixture was then shaken with butanol and the butanol layer evaporated to dryness. An oily substance was obtainedwhich.

emulsified in water. The oily material was taken up in a mixture of equal parts of methanol and water and then shaken with petrol ether. The

aqueous methanol layer and the petrol ether layer were dried separately and there were obtained:

12 parts of a water-soluble .waxy solid from the aqueous methanol layer and 34 parts of oil from the petrol ether layer.

An analysis of the solid gave the following result:

Chlorine, 0.85% Total sulphur, 13.74% Sodium sulphate ash, 35.85% indicating for its composition:

1.40% NaCl 9.24% Na2so4 and 89.36% of an organic sulphonated material,

containing 13.1% organically combined sulphur.

The sodium salt of an olefine sulphonic acid, derived from an olefine of the molecular weight of 222 would contain 9.86% organically combined.

sulphur, and a corresponding sulphuric acid ester would contain still less, indicating that the sulphonated compound obtained in a rather incomplete yield can only contain the sulphonic acid derivative of the original olefine in a small proportion.

Example ,8.-A solution containing 350 parts of ethylene chloride and 44 parts of 1.4 dioxane was cooled to 0 vC. and 65 parts of chlorsulphonic acid were added. while I maintaining the temperature at 0 C.

The reaction mixture was then cooled to -l0 C.

and while maintaining this temperature a mis tureof 100 parts of ethylene chloride and 112 parts of tetraisobutylene were gradually added while agitating.

After the completion of the charge, the masswas agitated for hour at -l C. and then neu-- tals precipitated from the methanol solution,

which were separated byflltration. The filtrate, on drying, left a white solid which is clearly soluble in water to give surface-active solutions. The yield of materials obtained was as follows:.

21.4 parts of unsulphonated oily material 28.1 parts of material, precipitated from the methanol solution which contained 14.8% organically combined sulphur and possessed the property of adding iodine.

The product was identified as diisobutylene sodium sulphonate. 7

106.1 parts of solids were obtained from the methanol filtrate which solids consisted of 3.6 parts of sodium chloride and 102.5 parts of a material, containing 9.5% organically combined sulphur and which also possessed the property of adding iodine. This product, therefore, consists of tetraisobutylene sodium sulphonate. The percentage yield of the theoretical is, therefore, as

follows:

63% tetraisobutylene sodium sulphonate 13.2% diisobutylene sodium sulphonate 19.1% unreacted tetraisobutylene (oil), with a total recovery of 95.3% of reaction materials.

Conducting the reaction at higher temperatures decreased the yield of tetraisobutylene sulphonate.

Example 9.-Into a solution of 300 parts of ethylene chloride and 52 parts of thioxane there were charged at 40 C. 60 parts of chlorsulphonic acid and then 84 parts of triisobutylene of the boiling point of 179 C. The reaction mixture was agitated until all solid matter had dissolved and then said mixture was neutralized at 10 C. with caustic soda solution After the removal of the solvents by steam distillation a clear solution was obtained which, on evaporation, yields a white, brittle solid which, according to analysis, is practically pure triisobutylene sodium sulphonate, containing approximately 12% sodium chloride as the only impurity. The solid exhibits surface-active properties.

Example 10.To a solution of 52 parts of thioxane and 300 parts of ethylene chloride there are added, under agitation 65 parts of chlorsulphonic acid, followed by '10 parts of a mixture of commercial diamylene of the boiling range 150 170 C. The reaction temperature is kept at 40 C. and the sulphonation is completed after four hours. .The reaction mixture is neutralized at 10 C. with caustic soda solution and the solvents removed by steam distillation. The remaining clear solution is evaporated to dryness. The solid obtained is a mixture of diamylene sodium sulphonates and small amounts of mineral salts and is clearly soluble in water. Its solutions have surface-active properties.

Example 11.-144 parts of commercial oieylchloride were added to the reaction product of 52 parts of thioxane and 65 parts of chlorsulphomc acid in 350 parts of ethylene chloride at 40 to so" and the mixture agitated until a homogeneous liquid was obtained. 'The reaction mixture was then neutralized with soda ash solution. The neutralized liquid separated into two layers, the lower containing the formed l-chlor- Q-octadecylene sodium sulphonate, dissolved in thioxane and ethylene chloride. This layer is separated and the solvents removed bysteamdistillation. The remaining aqueous solution is concentrated to yield the above named compound in the form of a soap-like brownish material which is soluble in water and which displays surface-active properties.

Example 12.-1nto 300 parts of chloroform containing the product formed by the action of 40 parts of sulphur trioxide and 52 parts of thlox- I sue, there were charged under agitation at 0 C. 56 parts of commercial di-isobutylene of the boiling point 100-103 C. mercial di-isobutylene. is:

% 2.4.4.trimethyl pentene-l. 20% 2.4.4.trimethyl 'pentene-2.

In the courseof one to two hours the solid sulphuretrioxide-thioxane product disappeared, indicating the completion of the sulphonation. The reaction mixture was neutralized with caustic soda solution and then steam distilled for the removal of the solvents. The residual opaque gel, on drying, leaves a brittle white solid which is di-isobutylene sodium sulphonate. It is sparingly soluble in cold and moderately soluble in hot iso-propanol from which it can be recrystallized in light needle-like crystals. The product forms lathery aqueous solutions of good wetting strength, and which product is identical with the di-isobutylene sodium sulphonate obtained as ,a by-product in Example 8.

Example 13.To the reaction product of 52 parts by weight of thioxane and 65 parts by weight of chlorsulphonic acid in 300 parts by weight of ethylene chloride there were added, at room temperature, 56 parts 'by weight of isooctenes of the boiling point 106-108 C.-which were obtained as the polymerization products of isobutylene with normal butylenes. After completion of the sulphonation the reaction mixture is neutralized with caustic soda solution and the solvents are steam distilled off. The remaining aqueous solution is evaporated to dryness to yield 106 parts of iso-octene sodium sulphonates, a white, brittle solid which can be ground to a powder. It is soluble in water and ethyl alcohol and difllcultly soluble in hydrocarbon solvents. It displays surface-active properties.

Example 14.Higher oleflnic hydrocarbons were prepared as follows: The polymerization The composition of com- 183 parts of fraction I were charged, atroom temperature into the reaction mixture obtained by. adding 90 parts of chlorosulphonic acid into the solution of 100 parts of thioxane in 200 parts of ethylene dichloride. After approximately 30 minutes a dark red solution was obtained which 175 parts of ethylenechloride and 52 parts of thioxane there were charged, at room temperature, 65 parts of chlorosulphonic acid. The reaction mixture was heated to boiling under a reflux condenser for 3 minutes to remove most of the hydrochloric acid vapors and then cooled to C. Then there were charged at once 17.5 parts of 2-pentene and the reaction mass heated to 50-60 C. and stirred until, in the course of two to three hoursall solids had dissolved. The reaction mixture was then neutralized at 10 C. by passing into caustic soda solution. The neutral solution separated into two layers; the aqueous layer, containing the neutral reaction products, is dried to give 88 parts of a white solid, which has the following composition: i

2.61% sodium chloride 13.5% sodium sulphate and g 83.89% of an organic material, containing 21.6%

organically combined sulphur.

A compound of e. g. the formula CH: CH CH CH: OH:

I olNa some contains 21.90% organically combined sulphur, whereas a 2-pentene sodium sulphonate contains 18.6% organically combined sulphur. The analysis indicates, therefore, that the greater part of the sulphonated material contained in theanalysed product consists of compounds which are more highly sulphonated than 2-pentene sodium sulphonate.

Example 16.I-Iigher oleflnic hydrocarbons were prepared from a mixture of decenes, commercially available under the name of diamylcues, in a manner described in the following.

Redistilled commercial di-amylenes of the boiling point 150-170 C. were polymerized at 0 C. in the presence of aluminum chloride. The aluminum chloride was removed from the resulting oil which after the separation of unpolymerized di-amylenes, was divided by distillation into three fractions 1 1'. Boiling at-10 mm. between 110-130 0. II. Boiling at 10 mm. between 130-170 C. III. Residue boiling at 10 mm. above 170 C.

198 parts of fraction I were charged at -10 C. into the reaction mixture of 65 parts of thioxane and 50'parts of sulphur trioxide in 525 parts of carbontetrachloride. After minutes of stirring the reaction mass was neutralized with caustic soda solution. The neutral solution was steam distilled for the removal of the carbontetrachlo- I ride and most of the thioxane. The residue was dried, taken up inmethanol and the methanol solution extracted twice with petrol ether. The methanol layer, on drying, left 204 parts of a yellow rubbery substance which is readily soluble in soft and hard water as well as in organic solvents. The substance is an excellent wetting agent and every effective detergent.

Example 17.-To a mixture of 350 parts of ethylene chloride and 78 parts of thioxane there were added 60 parts of chlorsulphonic acid. The

temperature was raised to 50? C. and 119 parts of heptadecylene were added. The heptadecylene of the boiling point l45-146 C. at 13 mm. was obtained by the dehydration of commercial synthetic heptadecyl alcohol by meansor sulphuric acid. After the completion of the *sulphonation,

the reaction mixture was neutralized with caustic soda solution and the solvents removed by steamdistillation. The remaining soapy jelly was evaporated to dryness and 161 g. of a pale yellow soap-like material were obtained. il'he material contains as its only impurity a small amount of mineral salts. It is soluble in water, alcohol and most organic solvents and has very valuable surface-active properties.

Example 18.--Into a solution of 52 parts of thioxane in 300' parts of carbontetrachloride there were distilled, from a flask containing fuming sulphuric acid, parts of sulphur trioxide. Into the reaction mixture, containing the insoluble addition product of sulphur trioxide and thioxane, there were charged at 20 C., 130 parts of a polyisobutylene fraction, boiling within a temperature range of 130-170 C. at 10 mm. mercury pressure. This fraction was obtained from a mixture of polymerized di-isobutylene formed by the action of boron fluoride on di-isobutylene of the boiling point of 100 -103 C. After one hour of agitation a clear wine-red solution was obtained, indicating the completion of the sulphonation. The reactionmixture was neutralized at 10 C. with caustic soda solution and the solvents were removed by steam distillation from the slightly alkaline mass until a clear gel was obtained which, on drying, yielded an almost white rubbery solid consisting of practically pure higher oleflne sulphonic acid salts. Traces of mineral salts may be removed from it by extraction with methanol, ethyl alcohol, benzene, a gasoline fraction or a like solvent. The extract, on evaporation, yields a mixture of pure oleflne sodium sulphonates which have been found to be extremely valuable surface-active products.

The above examples demonstrate methods of producing reaction products of thioxane with sulphuric acid derivatives and a few typical uses for which they may be employed. The examples 1 merely illustrate some preferred embodiments of our invention since it is obvious that; other sulphuric acid derivatives than sulphur trioxide or chlorsulphonic acid may be used. To cite a few others, we note that fluorsulphonic acid, sulphuryl chloride, methyl sulphonic acid and other compounds are useful sulphonating agents which may be used either alone in the presence of thioxane or in combination with hydrocarbons, ethers, polyethers, inorganic and organic acid anhydrides, acid chlorides and the like.

It is obvious that a great number of uses can -be found for our new'sulphonation aid. We cite for instance the sulphonation of hydroxy compounds to the corresponding sulphuric acid esters. Such esters have many applications and are employed as useful surface-active materials in many industries. They may be employed as chemical intermediates, as water soluble dyestuffs and as dyestuffs for the printing of textiles. It would lead this case too far afield to enumerate the different groups of hydroxy compounds the sulpho derivatives of which have become useful. Sufiice to say, however, our combination of thioxane with sulphonating agents may be employed in the treatment of primary, secondary and tertiary mono and poly hydroxy derivatives of substituted or unsubstituted aliphatic and aromatic hydrocarbons, of ethers, poly ethers, acids, esters, amines and other compounds.

The foregoing examples also show, that sulphonating agents in the presence of thioxane are capable of selective sulphonation of unsaturated hydrocarbons. Thus, our combination may be used with advantage for the selective sulphonation of aromatic hydrocarbons and for sulphonations under mild conditions in order to eliminate or decrease the formation of undesired by-products. It is, of course, obvious that the hydrocarbons to be treated may be substituted by halogen and/or nitro-groups and they may contain ether linkages, carbonyl groups and carboxylic acid groups which latter may be free or esterified.

Certain of the foregoing examples demonstrate some of the olefine sulphonic acid compounds of our invention and the procedures by which they may be obtained. Our examples furthermore indicate that although olefine sulphonic acid compounds may also be formed by sulphonating an olefine in the absence of thioxane, frequently in this case, especially when using higher olefines, a scission of the double bond of the original olefine occurs under the formation of lower olefines and olefine sulphonic acid compounds. Such a scission of the double bond prevents the complete sulphonation of an olefine when molecular quantities of the olefine and sulphonating agent are employed, whereas the use of an excess of sulphonating agent results in the formation of more highly sulphonated products which may be either compounds of the carbylsulphate type or sulphonic acids of lower olefines formed by the splitting up of the original olefines. sulphonating olefines of the types as specified above, in the presence of thioxane, however, leads to the uniform formation of sulphonic acid compounds of the unchanged olefines when one molecule of sulphonating agent or less is used per one molecule of olefine whereas the use of a a number of them in the form of their sodium,

potassium, ammonium or other salts of a monovalent base are highly surface-active materials in that they show great wetting, deterging and emulsifying strength. No attempt has been here made to define the'flelds of usefulness of the olefine sulphonic acids prepared as described above since the same would necessarily be incomplete and also quite unnecessary to a, complete understanding of the present invention. Suffice to say. said compounds have surface active or capillary active properties and may, therefore, be used to great advantage in any process involving wetting, penetrating, deterging, dispersing, emulsifying, deemulsifying, frothing, foaming, softening and like phenomena. The compounds may be used in pure or standardized form and alone or in combination with any known treating agents with or without the addition of other known materials having surface active properties.

This application is a division of our application Serial No. 260,330, filed March 7, 1939, matured as U. S. Patent No. 2,219,748 dated October 29, 1940.

We claim:

1. The process for the preparation of an alkylene sulphonic acid which comprises reacting an olefine with an addition compound of thioxane and sulphur trioxide of the formula:

CHs-CH:

wherein n is an integer from 1 to 2.

2. The process as in claim 1 in which the olefine is tetra-isobutylene.

3. The process as in claim 1 in which the olefine is di-isobutylene.

4. The process as in claim 1 in which the oleline is a polymerized isobutylene.

PAUL NAWIASKY. GERHARD EWALD SPRENGER. 

